Re: Storage controller access to data

[Kevin Wolf]

Am 12.10.2021 um 19:52 hat Nada Lachtar geschrieben:
> I’m working on a project that requires me to read the data being sent
> to storage and it to a file for analysis. To be more specific, I’m
> trying to analyze the data in the phase of being written to the
> storage disk, thus, I’m trying to read the data when it’s going
> through a storage controller on x86 device. I’ve been looking into the
> implementation of different storage controllers, but I need help to
> pinpoint where I can read such data.

Did you consider getting the data not from the frontend (i.e. the
implementation of the storage controller emulation), but from the
backend (i.e. the -blockdev configuration)?

For example, there is the blklogwrites block driver that creates a log
file that contains all the write requests that were made. Maybe this
provides already what you need.

If you need more flexibility than this, you could use an NBD connection
as the backend and have a custom NBD server that can process the data in
whatever way you need.

Kevin